BOSTON – Of all names, all the chants, all the songs that could’ve echoed from the rafters of this new Boston Garden during the NBA Finals – “Beat L.A.,” “Sweet Caroline,” maybe even a stray “MVP” chant for Kevin Garnett or Paul Pierce – there are only a few more unlikely than the one that took hold of the sellout, deliriously happy crowd here midway through the fourth quarter.

L-E-O-N P-O-W-E! L-E-O-N P-O-W-E!

That’s right, Leon Powe. Better known in most parts of the country as that guy who played at Cal a few years ago.

Since he’s come to the NBA, Powe has spent the majority of his time as a third or fourth big man off the bench, getting his name into the scorebook every night, but rarely for more than just a passing mention.

But Sunday night in Game 2 of the NBA Finals, there was Powe, at the free-throw line, soaking it all in as 18,624 fans stood on their feet, chanting his name in surprised glee during the Celtics’ 108-102 win.

“That was unbelievable,” said Powe’s guardian, Bernard Ward, who was sitting about 25 rows up from the court Sunday night. “I never in a million years would’ve thought that would happen. But that’s what all the hard work he’s put in did. He always stayed ready, always prepared, so he could do it if they needed him.”

Powe had the game of his young NBA career Sunday, scoring 21 points in just over 14 minutes of action. The second-year player made 6 of 7 shots from the floor and 9of13 free throws.

“I just know Coach called my number,” Powe said. “I was just happy to get in the game and be a part of this whole experience, because it’s been a long journey for me.”

He was more than just in the game. He was aggressive, he was effective, he was –

“Terrific,” Boston coach Doc Rivers said. “We had to go to Leon to establish a post game. And we made a concerted effort to get him the ball in the post – and he responded.”

Powe, who stands 6-foot-8, had averaged just 4.6 points and 12.6 minutes in the playoffs before Sunday. In Game 1 on Thursday he played just nine minutes and scored fourpoints.

Game 2 was an entirely different story. ABC aired a moving, emotional feature on his hard-luck upbringing on the streets of Oakland during halftime. Powe was homeless for several years after his family’s house burned down, then was taken from his mother and placed into foster care in middle school. Ward became his guardian in the sixth grade and the two have remained close ever since.

The story was filmed twomonths ago, but Ward said ABC told him it was so good, they wanted to save it for the Finals. That they picked halftime of Game 2 to show it was either incredibly fortuitous, or an incredible twist of fate.

On Sunday, Ward sat next to DeVon Hardin, Powe’s former teammate at Cal who was in town for his own workout with the Celtics this weekend. Neither could believe their eyes as they watched Powe have a breakout game.

“With Leon, it’s not about size, it’s about heart,” Hardin said. “He’s the toughest player out there on the court. He’s shown glimpses of what he could do before, just glimpses. But tonight, wow, he was unbelievable.”